This invention relates to aid devices for cardiac resuscitation, more specifically to devices and methods to improve blood return to the heart in patients that are victims of cardiac arrest.
Backboards have been part of the armamentarium of emergency care for many years. Every ambulance carries a backboard. Backboards have their place in emergency care because they are essential to the immobilization and transportation of patients with suspected spinal injuries. The other major indication and use of backboards in emergency care is in the field of cardiac resuscitation. As taught by the American Heart Association, in case of cardiac arrest for resuscitative efforts the victim must be placed supine and on a firm flat surface in order to optimize external cardiac compression. It is accepted practice to place the victim of a cardiac arrest on a hard and unyielding surface such as the floor or the ground prior to initiating cardiopulmonary resuscitation. If the victim is on a bed or an ambulance stretcher, a backboard is always placed under the patient""s back by a paramedic, physician or nurse. Indeed attempting to compress the patient""s chest while the patient lays on a mattress or other non rigid surface will result only in pushing the patient""s whole body downward during external cardiac compression, without achieving the desired chest compression. Backboards are therefore widely used nowadays as an important adjunt in emergency cardiac care.
External chest compression provides circulation to the heart, lungs, brain and other organs as a result of a generalized increase in intrathoracic pressure and/or direct compression of the heart against the thoracic spine. During cardiac arrest, properly performed external chest compression can produce systolic blood pressure peaks of more than 100 mm Hg, but the diastolic blood pressure is low. The goal of cardiopulmonary resuscitation is to provide blood flow to vital organs until more definitive care such as defibrillation and pharmacological therapy can be provided. Many patients have extremely poor perfusion during CPR. Several alterations in the technique of CPR have been proposed to improve hemodynamics: CPR and with elevation of the lower extremities, Interposed Abdominal Compression IAC/CPR, High-Frequency also called Rapid Compression Rate CPR. Mechanical devices that can be used as substitutes for manual chest compressions have also been developed such as Cardiac Press, Automatic Resuscitators, Pneumatic Antishock Garment, Vest CPR, and Active Compression-Decompression CPR.
A major problem, if not the number one problem of poor perfusion during CPR, common to all the above techniques and devices, is the insufficient/inadequate venous return of blood to the heart. Indeed, it is well known that diastolic filling during CPR is only a fraction of the diastolic filling of the pre-arrest condition. The inventors, experts in the field of resuscitation, are unaware of any CPR technique or device that promotes adequate diastolic filling such as the one subject of the invention. Indeed an extensive search in the pertinent medical literature and in the Patent Office failed to disclose any apparatus or method for improving diastolic filling of the heart by gravity during cardiac arrest such as the apparatus and method disclosed in this invention.
With the present invention the inventors propose a simple solution to the problem of insufficient diastolic filling during external or open cardiac massage. Essentially, the invention uses gravity in order to enhance blood return to the heart from the lower extremities, from the pelvis, from the abdomen, from the upper extremities and from the head.
The present invention comprises a tiltable backboard for cardiac resuscitation which promotes venous return by gravity during external or internal chest compression. It consists of a standard backboard made of plastic or wood or any suitable rigid material provided with a feature or a mechanism which permits adjustable tilting with respect to the flat surface of a floor or a bed or a gurney.
The backboard is also provided with the capability of tilting the head of the patient forward with respect to the remainder of the body. In use the body of a patient who is a victim of cardiac arrest is placed supine on the board. The board is tilted by a certain degree by raising the distal end so as to position the body of the patient inclined with his chest down and his feet up. The head of the patient can be tilted forward to promote blood return from the head to the heart. Being the patient positioned with the feet up and the chest down, so that the lower extremities are higher than the pelvis and abdomen and tilted down toward the pelvis and abdomen, and the pelvis and abdomen higher than the chest and tilted down toward the chest, the blood within the venous system of the lower extremities and the pelvis and abdomen will move by gravity toward the chest into the heart promoting diastolic filling. Being the head flexed forward in respect to the remainder of the body, and therefore positioned higher than the heart, the blood in the venous system of the head will be draining downward to the heart by gravity.
The angle of inclination of the tiltable board is adjustable from zero degree to 60 or more. This invention provides a simple means of promoting a blood return into the heart in patients victim of cardiac arrest when external or internal cardiac compression is applied.
It is an object of the present invention to provide a simple, rapidly deployable and effective means of promoting venous blood return during external or internal CPR.
It is an object of the present invention to provide emergency care workers with a simple effective apparatus and method for improving diastolic filling of the heart during cardiac resuscitation.
It is an object of the present invention to provide emergency care workers with a simple and effective apparatus and method of improving diastolic filling and cardiac output during external or internal cardiac massage.
It is an object of the present invention to provide emergency care workers with a device which is very simple to deploy and use at the scene of a cardiac arrest whether the arrested patient lays on the floor, on a bed, or on a gurney.